The permanent rupture between the Roman Catholic and Eastern Orthodox churches when the Pope and Patriarch excommunicated each other in 1054. Brownworth frames this as the event that set the wheels of the First Crusade in motion 42 years later, since it established the Pope rather than the Byzantine Emperor as supreme spiritual authority in the West — meaning Alexios' appeal to Urban II for mercenaries gave the Pope the opportunity to call a crusade under his own authority.
What each episode says
Episode 14 (2 mentions)
The permanent rupture between the Roman Catholic and Eastern Orthodox churches when the Pope and Patriarch excommunicated each other in 1054. Brownworth frames this as the event that set the wheels of the First Crusade in motion 42 years later, since it established the Pope rather than the Byzantine Emperor as supreme spiritual authority in the West — meaning Alexios' appeal to Urban II for mercenaries gave the Pope the opportunity to call a crusade under his own authority.
“in what came to be called the Great Schism.”
“With the Great Schism, however, the West had rejected that claim, and the implications”
Related